


Come Together

by Tallulah_Danger



Category: The Infernal Devices Series - Cassandra Clare, The Shadowhunter Chronicles - All Media Types
Genre: Anal Fingering, Anal Sex, Angst, First Time, First Time Blow Jobs, First Time Bottoming, Fluff and Angst, M/M, Top!Jem
Language: English
Status: In-Progress
Published: 2021-01-21
Updated: 2021-01-21
Packaged: 2021-03-13 09:14:55
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 4,236
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28900983
Author URL: https://archiveofourown.org/users/Tallulah_Danger/pseuds/Tallulah_Danger
Summary: Jem and Will discover their feelings for each other. Sex ensues. Largely fluff except for the end, which almost made me cry writing it.
Relationships: Jem Carstairs/Will Herondale
Comments: 10
Kudos: 25





	Come Together

**Author's Note:**

> Top!Jem back by request.

Jem had patience. Jem had enough patience to run everyone in the Institute through all of their annoyance and pain. Will Herondale was going to run through Jem's patience in one night. 

It was not that Will was exceptionally self adoring or considered himself above work, like Jessamine. He simply would not stop talking. He flirted with mundane girls, he complained to Charlotte, he contested everything Jem said. He made fun of mundane boys behind their backs, and commented on every outfit on the street. 

Jem had known Will for four years, and was largely considered to be the one person who could handle Will. Jem enjoyed Will's company usually, though he could be abrasive. But tonight, Will would not stop talking. 

He had talked all through patrol, which was uneventful aside from a werewolf stalking a mundane family. He had talked, exchanging what was certainly witty repartee with the werewolf as he took him down. Jem had to hide his smile as Will made joke after joke. 

That was the worst part of it. Will was funny. He made Jem laugh often, made him feel more sprightly on his worst days. 

When Will had bounced back to Jem, hair missed and cheeks flushed, that hint of adrenaline behind his smile, Jem had felt a little unsteady. 

He would have, Jem thought, been able to quite happily be parabatai with this boy had it not be for his smile. And his hair. Whenever Will gave him that buoyant smile, Jem felt like the world was tilting slightly. 

Will, oblivious to Jem's already impeded balance issues, talked all the way back to the Institute. He gave the report to Charlotte on what had happened, and then right as Jem had felt stable enough to add in the more boring details, Will had run a hand through his hair and glanced back at Jem. 

Jem simply nodded along with Will's story and knew very well that important things were being left out. He would go to Charlotte later and answer any questions she had. 

Then Will said, ebullient tone sharpening, "Had you been listening, Charlotte, you would know I already answered this." 

Jem sighed through his nose and let out a quiet, "Will." 

Will turned to him. Jem wished he had appreciated the high that patrols gave Will, because his eyes were hard now.

Will snorted and left the library. Jem's head cleared. No, this was the worst part of being Will's parabatai. The cruelty that always seemed to surface. The cruelty that sharpened his smile and dulled his eyes. 

There is hope for you yet, Will Herondale.

Jem turned back to Charlotte.

"I must apologize for Will. You know how he gets."

Charlotte gave him a piercing look.

"Someday, Will won't have you to apologize for him. He needs to learn how to take better care."

"You think I don't know that?" Jem snapped, then took a deep breath. Charlotte looked horrified. 

"I did not mean-"

"It is alright, I am sorry for being rude."

"No." Charlotte shook her head, pressing her hands together. "I did not mean your illness. I simply meant Will cannot always have you by his side." 

Jem simply bowed his head and left the room.

…

"You should apologize to Charlotte." 

Jem leaned against the doorframe, watching as Will slammed seraph blades into their rack. Will stayed silent and continued to put weapons away with as much force as possible. 

"What for?" He finally asked, managing to line every syllable with disdain. 

"You were quite harsh." 

"She was not listening." Will turned around, eyes blazing. "Want to spar?" 

Jem hesitated, torn between accepting the offer and trying to continue. He finally set down his cane by the door and shook his limbs out. 

Will grinned and made his way to the center of the room, getting in fighting stance. Jem followed, albeit slightly slower. He hadn't done anything on patrol, but it still drained him. 

They circled each other. Predictably, Will struck first. Jem deflected, not returning the attack. 

"Tell me, you looked slightly ill after I took down the werewolf. Why was that?" 

That was when Will had smiled back at Jem. Jem tried to think of a way to deflect. 

"Watching you fight drains me." At that moment he moved, getting a hit in right below Will's ribcage. 

"Because I'm so good at it?" Will tried to hit back but only managed to strike Jem's forearm. 

"Because you add in so many unnecessary flourishes." 

Will laughed, then charged. They grappled for a bit, getting and losing grips on each other's arms and waists. Right as Jem began to have to work to catch his breath, Will managed a grip tight around his stomach, arms slightly lower than Jem liked. 

"Getting tired yet?" 

Jem braced his feet under himself and managed to twist around. He spun, slamming into Will. Will gasped, but Jem was already moving. Within seconds Jem had Will pinned against the wall. 

Everything was quiet for a long moment. Will was staring at Jem in shock, eyes huge. His mouth dropped slightly. Jem didn't think it was that surprising that he had managed to pin Will, especially considering he had been a shadowhunter for longer than Will. But Will was staring at him like someone had told him the Institute doors were missing. Shocked and confused and a little horrified. 

"You should respect your elders." Was all Jem said. 

"Still harping on about Charlotte?" The shock was replaced with annoyance. 

"Me," Jem said, grinning. 

Will laughed softly, and it was when Jem could feel the vibrations of his laugh that he realized how close they were. How mussed Will's hair was. How pink his cheeks were. 

Jem took several steps back, releasing Will. He went to get his cane, needing to get out of there before a problem arose. And one was. Very quickly. 

"There's that look again," Will called. "Did you do too much? You should rest." 

"Thank you, I will do that now." An excellent opening for Jem to leave. 

"You know." Will kept talking. Angel above, why did Will talk so much? "You get that look after I fight. Whether you fought as well or not. You get it often, if I am remembering correctly." 

"I must rest," Jem said, in a final attempt. Will narrowed his eyes, looking like something was dawning in his mind. 

"I will have Sophie bring you tea," Was all Will said, and Jem nodded. As he walked away, he desperately hoped that Will's utter lack of ability to determine how others felt would make itself useful here. 

…

Jem let himself be lost in the notes as his bow danced over the strings. He had discovered that playing his violin helped calm him down after his encounters with Will. Jem hit a note sharper than he intended, pressing down too heavy. He took a deep breath and put thoughts of Will out of his head. 

Someone knocked on Jem’s door right as he caught the melody again. He sighed and set his violin and bow down. 

“Come in.” 

The door opened and Will sauntered in. Jem gave him a look of fond exasperation. 

“I didn’t mean to interrupt your playing.” Will strode over to Jem. Jem tried desperately not to stare at Will’s long legs. “I just came in to tell you that I am a kind and generous person.” 

“Oh?” Jem didn’t bother to keep the incredulity out of his voice. 

“I apologized to Charlotte.” Jem turned, eyebrows raising. “Oh, don’t give me that look. It makes me think you think I am an awful person.” 

Jem refused to respond. Instead, he simply crossed his arms and asked,

“What did you say?”

“I apologized.” 

Jem sighed. He knew that Will wouldn’t say another word about it, knew that it had taken pressure to make him apologize in the first place and that he most likely wanted to forget about it. 

“She hugged me.” Wil sounded affronted, and Jem stifled a laugh. Will cast his eyes skyward and Jem let his gaze linger. 

Will was only wearing his shirt and trousers, and Jem was slightly annoyed at how easy his brain could conjure up images of him being in less. Will dropped his gaze and met Jem’s eyes. 

“But you apologized.” Jem’s voice was softer than he intended. Will laughed a little and shrugged. 

“You are my conscience, James Carstairs.” Will took a casual step closer. “You can see when people are hurt, and you know that I must apologize.” He took a few steps more, seemingly unconsciously. Jem was very, very conscious of how close he was. “You know I cannot apologize to people, you know how it would end. You know-” He broke off. 

“What do I know?” Jem straightened, trying very hard to keep his eyes on Will’s. 

“Nothing.” Will seemed to pull out of his daze. He looked like he wanted to flee. “You know nothing.” 

“You aren’t too observant, either.” Will scoffed. 

“Name one thing I haven’t been able to detect.” 

Jem swore that Will was going to be the death of him. Will was close to him and his cheeks were pink from the warm fire and he had just shown actual human decency and Jem was praying to the Angel that Will did not look down. There was something Jem hoped Will wouldn’t detect. 

Will took another step toward Jem. 

“You can’t think of anything,” He gloated. “You can’t think of a single thing I haven’t noticed.” 

Jem couldn’t focus on anything. He would not ruin this, he absolutely would not. Will smirked and tilted his head. 

“I can think of something you are a little oblivious to, however.” Jem raised an eyebrow, and then Will snagged Jem’s collar in one hand and kissed him gently.

Every thought left Jem’s head. He would not have been able to answer the simplest of questions had someone asked him. Will began to pull away, and Jem’s mind caught up. He chased Will’s mouth and kissed him back. Will made a surprised noise, but Jem was determined. If this ruined everything from here on out, Jem was going to make this the best damn kiss of his life. 

Jem did not consider himself a good kisser. He had not had much practice, aside from kissing a single werewolf girl last year. He still had the advantage of surprise on his side. Jem tried to be sweet, tried not to ruin this too much. But then Will was kissing him back and Jem could care less because WIll’s mouth was perfect. Will’s other hand drifted behind his neck and tugged him closer. Jem slid his hands over Will’s shoulders. Desperately wishing there was skin under his arms instead of his shirt, he twisted his fingers in the loose cloth. 

Will seemed to want the same things, because he slid his hands to the buttons on Jem's shirt. Jem made a low noise as Will popped button after button. He pulled back slightly to run his hands over Jem's chest. 

"Just so you know." Will sounded slightly breathless. "I like to top." 

Jem froze. Then he very slowly began to undo Will's shirt as well.

"We'll see." 

Will laughed softly, and then they were back at it, Will biting Jem's mouth lightly and Jem shoving Will's shirt to the ground. Any hint of exhaustion was long gone. Will managed to turn them so they stumbled to the bed, and Jem was disappointed in himself for not doing this earlier. The idea of anything that Will could possibly want to do on a bed made Jem slightly lightheaded. 

Will's hands were at Jem's pants and Jem clutched at Will helplessly. Jem lifted his hips, almost unconsciously, for Will to slide his trousers down. Will hesitated, looking unsure. So Jem reached out with his deft fingers and undid Will's belt. 

"Wait."

Jem drew back instantly. 

"My apologies, I-"

"No." Will shook his head, looking firm. "I just have done at least this before." 

He dropped to his knees and pulled Jem closer to the edge. Jem was utterly lost, until Will reached out hesitantly. Oh. 

Jem made sure not to shut his eyes as Will leaned over and very gently kissed Jem's tip. And when Jem very lightly took him in his mouth, Jem saw stars. 

He had thought seeing Will with his cheeks pink and hair mussed flustered him. Jem had thought that seeing Will fight turned him on. There was absolutely no way any of those could compare to Will sucking him off.

In spite of himself, Jem's eyes fluttered shut. Will was warm and wet and Jem was not going to last the next five seconds. He opened his eyes and tugged on Will's hair. 

"Will-"

Will popped off and Jem almost blacked out. His mouth. 

"Yes?" 

"Get up here. Now." Will obeyed instantly. Jem shoved down Will's pants with no ceremony and was slightly taken aback. Will was hard. Hard enough it looked like it hurt. 

Jem vaguely knew what to do. He wanted to be inside Will now, but from what he knew of girls they needed to be stretched out first. Boys probably needed that, too. 

"Sit down," Jem ordered. Will sat. Jem was beginning to doubt Will's earlier statement. 

Jem trailed a hand down Will's back, then over his ass. He stopped, realizing something. He brought one hand up and spit in it. Will made a small sound, and Jem looked at him quizzically. Will was staring, open mouthed. 

"What?" 

Will made a helpless gesture. "You. Are you going to put your fingers in my ass?" 

Jem felt himself flush. "Yes."

"Angel above." Will made another gesture. "Get to it, then." 

Jem obliged, moving his now slick fingers to Will's entrance. He raised an eyebrow at Will, who nodded emphatically. Jem hesitantly pushed one finger in. 

It was warm. Feeling Will clench around him was more arousing than Jem was expecting. Jem gave an experimental curl of his finger. Will groaned. Jem did it again, pleased. 

"More," Said Will, through gritted teeth. Jem grinned and slipped another finger in. This time, Will's sound was more of a whine. 

"You have absolutely no idea how beautiful you look right now." The words slipped put without Jem meaning them to, but Will's mouth was open and he was panting slightly and his knees were braced against the bed. What Jem was not expecting when he spoke was for Will to turn an even brighter pink and make a breathless noise. 

Jem hummed and tried something. 

"You look gorgeous, always, but especially with your knees spread like that." 

Will clenched around his fingers and moaned quietly. Jem kept pumping his fingers. 

"Do you like when I call you pretty? How about when I say that you are wonderfully tight and I can't wait to be inside you?"

"Please," Will begged, body arching as Jem reached deep. 

"What were you saying about how you always top?” Jem smiled at him, then gave his fingers a little wiggle. Will gasped, hands bracing against the bed. Jem found himself fascinated by the fact that Will made so many noises. He had assumed Will would be as put together as he normally was, but that assumption was being proven wrong staggeringly quickly. 

"Jem," Will forced out, breath coming out sharply. "Do you have an actual plan or are you just going to sit there?" 

"I do have a plan." Jem kept slowly scissoring his fingers. Will shifted, looking impatient. He waited, making soft little noises, before opening his mouth. Jem assumed he was going to complain and decided it was the perfect time to add in a third finger. 

Will made a harsh noise that sounded like someone had punched him in the gut. Jem was enjoying this immensely. Jem moved his fingers, trying to stretch Will out enough. Right as Will looked like he was going to collapse from the strain of holding himself up, Jem pulled his fingers out. All three of them.

"Hey!" Will sound affronted as he gathered his wits and glared at Jem. Jem simply smiled serenely and shoved himself further onto the bed. 

“My plan, Herondale, is for you to lay down and for me to pound you into the bed.” 

Will stared, open mouthed. Then he exploded into motion, flinging himself onto the bed with much drama. He stared up at Jem, quirking one eyebrow, and said lazily, 

“Get to it, then.” 

Jem snorted and shifted, situating himself beside Will’s legs. Then he gently lifted one of Will’s knees, propping it up and spreading it to the side. Will instantly copied the motion with his other leg, leaving himself spread wide and on display. Jem sucked in a breath. 

“You-” He shook his head. “You’re so perfect.” 

Will smirked. Jem decided right then and there that there were better uses for Will’s mouth. He maneuvered himself to be in between Will’s open legs, examining him in all of his nakedness. Will looked slightly nervous, shifting awkwardly, so Jem ran a hand down Will’s thigh. Will sighed, relaxing ever so slightly. Jem let his hand trail down to Will’s hip. When he grabbed at Will, Will jumped. Jem stroked, going slowly, trying to ease Will into this. 

“Oh, just get inside me already.” Will sounded exasperated, and Jem hid his smile. He spit into one hand, stroking himself, then lined himself up. He waited, looking at Will let out a long breath, then nodded. Jem began to push in, gently. He got about halfway in when Will lost patience. 

“James Carstairs, you better stop being slow and start fucking me.”

Jem thrust in and bottomed out. Will let out a loud enough groan to vibrate Jem's hand where it was set against his thigh. Jem pulled out slowly and thrust in again, trying to be gentle. Will's eyes squeezed shut, and his breath was coming in short little pants, exhaling every time Jem thrust in and pulled out. Jem wanted to just stare at his face. 

"Hurry. Up." 

Jem gave a few more short thrusts, just to tease, then sped up a bit. At one thrust, Will yelped. Jem instantly pulled out.

"Did I hurt you?" 

"Angel above, no." Will stared up at Jem through his wild hair. "Whatever that was, do that again." 

Jem smiled and slid himself back in. He tried to aim where he had before. After a few tries, Will gasped. 

"There." He braced his hands against the bed. "Hit right there." 

Jem made sure he did. Seeing Will like this, splayed open, panting, looking so disheveled, made Jem just want to fuck him into the bed. 

"You look gorgeous." 

The words were out, and at Will's little whimper, Jem didn't try to hold them back. 

"I have dreamed about doing this for ages. You asked earlier why I always look flustered after seeing you fight? It is because you are so fluid." 

Jem was fast losing the ability to hold this steady stream of words.

"You look so fluid and capable and I imagine how you would look if you were in. my. bed." He punctuated the last words with extra deep thrusts. "And now I know."

The sounds Will was making were enough to drive Jem insane. Little whimpers and moans that might've been Jem's name. Jem found himself hurtling fast towards the end, and slowed his pace. Will opened his mouth, but Jem beat him to it. 

"We come together. Always." 

Will's mouth fell open, but he just nodded. Jem reached a hand between them and brushed at Will's cock. Will's reaction was immediate; he jerked like someone had slapped him. Jem made another tentative motion and Will moaned. Jem decided this was most likely on the right track and grabbed ahold. 

Jem managed to shift his weight to be more comfortable. Will was hard as a rock and looked like he was going to pass out any second, and Jem didn't feel much differently. One of Will's hands drifted up, probably to try to grab hold of his own cock, but Jem grabbed his wrist instantly and shoved it back to the bed. He gave an additional firm press at the same time as he swiped his thumb over the tip of Will's cock, and then Will was climaxing. 

He clenched tightly around Jem, warm and wet and tight, and Jem came with a cry. 

They stayed there for a second, then Jem pulled out and sat back. He stared, uncertain what to do. 

"Come here," Will demanded, one arm lifting shakily. Jem layed down.

Curled against Will, Jem couldn't believe he hadn't tried this before. Will was soft and pliant and loving, and Jem exhaled slowly and he realized he well and truly loved this boy. 

Will turned his head and caught the end of Jem's smile. 

"What?" He whispered, and Jem folded himself closer, tucking Will's head under his chin. 

"You just look lovely all fucked out." 

"You have a filthy mouth, Jem Carstairs. I think I like it." 

They sat in silence, and Jem wondered if the Angel had been especially kind in gifting him Will. 

"You know what they say." 

Jem breathed in the scent of Will. "What?" 

"Sex makes the world go 'round." 

"I thought that was money. Or alcohol, for you." 

Will laughed and pushed at Jem's side. Then his warm breath tickled Jem's neck as Will kissed his collarbone. Jem startled, and Will pulled back. 

"I liked it," Jem said, trying to sound nonchalant and not like he was aroused enough to go another round. 

Will tucked himself back in and pressed his mouth gently to the juncture between Jem's neck and shoulder. He kissed everything he could reach, and Jem silently added this to a list of things he liked very much. 

They fell asleep like that, dozing, cuddled together, pressing sweet kisses to each other. Jem thought he could very much get used to this. 

…

Will startled awake. He was warm and comfortable and surrounded by the smell of burnt sugar. It took him a moment, groggy as he was, to remember where he was. When he did, a rush of joy filled him. Jem, his Jem. 

Will pulled back slightly to look at Jem's profile. He was asleep, looking so peaceful and content. Will smiled gently, and reached out a hand to brush away some hair from his eyes. Jem turned before he could, stirring in his sleep. He coughed, whole body racking with the force, and when he turned his mouth away from the pillow, there was blood on the white sheet. Will froze, then shoved himself up and away from Jem. 

Jem awoke with a start, looking around wildly. He blinked at Will, now standing. Will stared down at him, feeling odd. Then that familiar coal pit of anger began to burn in his stomach. He turned away and began to search about for his clothes. 

"Will?" Jem's voice was full of sleep. "What are you doing?" 

Will forced levity into his voice. "I'm leaving."

"...Why?" Jem asked, when Will didn't say anything extra. 

Even though it killed him, Will scoffed. "We fucked. That was nice. But it didn't really mean anything." Jem was silent, and Will kept talking as he shoved his pants on. "It can't mean anything, you know that." 

"It could. It isn't like you don't break the law constantly anyway." 

"It's not just the Law!" Will whipped around, not caring he was shouting. "You're dying and I have my-" He broke off and stood there, trembling. "Besides. It was a nice fuck. Shame to mess that up with something we don't want." 

He couldn't look at Jem. Didn't want to see the expression there. 

"You have your what?" Jem asked, voice calm. 

"It doesn't matter." Will grabbed his shirt from the floor and dove into it. "This was fun. Maybe we'll do it again." He saluted to Jem, who was lying perfectly still. Then he walked out, despising himself all the more as he heard what may have been a sob behind him. 

…

"Stupid, stupid, stupid!" Will kicked his bed frame. He placed his room, furious. Will had never hated anyone so much as he did himself in that moment. It had been perfect. Jem had fit perfectly around him, he had smelled perfect, the look on his peaceful, sleeping face had been perfect. 

"Fuck!" 

He slammed his hands down on his washstand and glared at himself in the mirror. He examined his wild hair and narrowed eyes, then his gaze dipped to something poking out of his collar. He yanked his shirt down and stared at the mark there. Jem must've left it at some point. 

Will shoved himself away and stalked towards his wardrobe. He wrenched open the doors and blindly grabbed the first coat that came to hand. It was a dark blue one, one Jem had gotten for him at his sixteenth birthday. He threw it across the room and grabbed a plain black one, shoving his arms through the sleeves. He didn't bother with a vest or cravat, not even grabbing a top hat or walking stick before storming out of his room. 

He was going to get blackout drunk, he decided, and there was a savage comfort in knowing Jem wouldn't come looking for him.

**Author's Note:**

> This will be the first in a thrilling saga of Heronstairs smut. Jem will mostly top. You're welcome.


End file.
